Method and apparatus for conditioning air



May 3, 1938. R. T. SMITH 2,116,480

METHOD AND APPARATUS FOR CONDITIONING AIR Filed Jan. 17, 1936 2 SheeLS--SheefI l May 3, 1938. R. T. SMITH 2,116,480

METHOD AND APPARATUS FOR CONDITIONING AIR Filed Jan. 17, 1936 ZSheStS-Sheet 2 jgs- f lll m Patente-d May 3, 1938 UNITED STATES PATENT OFFICE METHOD AND APPARATUS FOR. CONDITION- ING AIR Russen r. smith, Richmond, Ina., assignmto.

Climax Machinery Company,

Indianapolis,

Ind., a corporation of Indiana 12 Claims.

proposed for treating air in an occupied vspace to produce more comfortable conditions for occupants. `These known'methods and arrangements of apparatus, where lower temperatures of the air were to be achieved, have been directed to one or some of the problems involved in air conditioning and as provided quitegenerally employ l5 some air circulating means together with refrigeration for dehumidifying and cooling the air to a predetermined temperature. 'The dehumidication accomplished in the prior arrangements was chiefly that obtained as a natural result due -to circulating the air over a cooled coil with little attention being given to the amount of moisture extracted from the air. Such arrangements,

while sometimesfunctioning satisfactorily to" produce a desired temperature difference, did not result in comfort cooling for occupants within `the enclosure.

' The problem of conditioning air for human occupancy to obtain satisfactory conditions resulting in comfort cooling for occupants involves much more than mere regulation and control of temperature and humidity. Air in any occupied space and within an enclosure lbecomes fouled with malodorous impurities and minute particles in suspension which must be dealt with and the electrical state of the air with its positive and negative ions is a matter of great importance. It has been determined that an occupant of any room can be very comfortable therein when a lower relative humidity is maintained regardless 0 of temperature difference between outside air of cooling to provide comfortable conditions with- 50 out the attendant shock experienced in passing to and from an over-refrigerated space.

One of the primary considerations in air conditioning being the removal of moisture from the air especially /during the summer months, this .55 has led in some arrangements operating with a dehumidifying phase, to` the use of commercial type of refrigerating apparatus including a conditioning evaporator comprising a coil with fins initially cooled below dew point and over which m the air is passed for the purpose of allowing the Application January 17, 1936, Serial No. 59,623

(Cl. G2-176) moisture to condense out on the surface of the coil. Thisarrangement in prior structures has been found impractical and inefficient for the v moisture condensed out of the air on the coil and finsinto small drops or beads and accumulated 5 on the fin surfaces of the coil to the extent of insulating the coil or n surface from the air which passed over it. It has been found that the accumulation of moisture condensed on the air conditioning evaporator of the ordinary type 10 will insulate the fins temperature as high as eight degrees differential. For example, with a v coil maintained at 40 degrees temperature with moisture accumulation, the air passing over the ns will show a temperature of 48 to 50 degrees 15 which is a denite loss of heat exchange and efficiency. This insulation of the coil fins by ac cumulated moisture soon carries the air contacting surface above the dew point and no more condensation takes place with the result that the 20 only moisture removed from the air was that which took place in the first few minutes after starting with an extremely dry coil and dry n surface.

Thepresent invention contemplates the pro- 25 duction of a complete air conditioning system with the cooling evaporator so constructed and arrangedwith respect to the circulating means that condensation is removed downwardly from the iin coil as it accumulates so that the fin coil '3'0 may be maintained below dew point toV provide continuous dehumidication and increased efficiency. Furthermore, the present invention is directed to an arrangement wherein that portion of the air passing through the evaporator-is first 35 filtered and after leaving'the evaporator is tempered with a portion' of recirculating air from'. the enclosure and is puried with a portion'of air which has been subjected to an ionizing process. The inclusion 'of the ionization phase of the sys- 40 tem aids the functioning of the filters and puriies the air, eliminating therefrom all odors tending to accumulate in the enclosure.

In prior air conditioning arrangements, it has generally been thought necessary to bring in from v unit is used.

A further object of the invention is the provision of a system wherein air circulated from the apparatus is delivered by an oscillating fan in the lower strata of the enclosure without creating a cold draft on an occupant.

A further object of the invention is -the provision of an air conditioning unit in which the air contacting surfaces of the evaporator are maintained below dew point and free from accumulated moisture.

Another object o1 the invention is the provision of a unit having means therein for purifying the air in an enclosure by ionizing a portion of the air conditioned.

These and further objects and advantages of the invention will become apparent from the fol-v lowing description and speciiication wherein reference is had to the accompanying drawings lforming part of the specification. Like reference characters represent similar parts throughout the several iigures of thedrawings, wherein- Figure 1 is a front view of an air conditioning unit embodying the invention enclosed within an ornamental cabinet or casing.

Flg. 2 is a rear elevation ofthe unit' of Fig. l,

with the back panel of the casing removed to disbodiment of the invention, a cabinet or casing Il forms a housing support for the structural organization of the air conditioning apparatus. The vspace within the cabinet is divided into an upper compartment 2 and a lower compartment 3 by horizontal partition 4 which serves also as a supporting shelf for portions of the apparatus located in the upper compartment which actually deal with the air entering and leaving the 'cabinet in the air conditioning circulation. Suitable insulating material 5 oi heat and sound deadening character insulates the lower compartment 3 from the upper compartment and air circulated in the lower compartment is precluded from entering the upper compartment. The lower compartment contains the refrigeration equipment or unit commonly termed the high y side of the cooling apparatus. This refrigeration equipment is supported on a metal base frame 6 on resilient sound deadening supports 1 on the bottom of the casing or cabinet. The refrigerating unit comprises a compressor 8, motor 9 in driving connection with fan I0 and with the compress'or by belt II, condenser I2 and the receiver I3. One end of the condenser coil is connectedV with the outlet of the compressor and the other end is connected with the receiver. The condenser comprises concentric conduits, the innermost carrying refrigerant and the outer conduit carrying cooling water. The circulating fan Ill driven byu the compressor motor causes the air within the lower compartment to be impinged on the outersurface of the cooling coil of the condenser so as-to provide a heat exchange relationship which practically dissipates the heat in the lower compartment by the absorption of the,

heat by the cooling coil of the condenser, so that the lower compartment and apparatus therein is maintained comparatively cool.

A narrow horizontal rail or panel I4 upstanding from the bottom of the cabinet and connected between spaced sides of the c abinet serves as a support for the lower edge of the rear closing panel I5 and also supports water inlet and outlet connections I6 and I1, respectively, for the condenser coil and an electrical connectingldevice I8 in the form of a plug in connector iitting to receive a conventional connecting plug attached to a flexible conductor cable from a suitable source. A junction box I 9 is electrically connected with the current supply connector I3 by cable 20 and has therein a safety fuse 2I for distribution circuits from the box. Electrical connections for motor 9 comprise current cable` 15 22 extending from the junction box to the terminal connections for the motor, and suitable conductor cables 23 and 24 also extend from the junction box into the upper compartment 2 for energizing connection therein with an oscillating air circulating fan and an ionizing device later to be described. Appropriate switch control for these circuits are provided through connections 25 with switches 26 having their operating elements disposed on the outside of the cabinet.

'I'he refrigerating apparatus or unit may be of any type desired. This unit as illustrated is of the compressor-condenser-expander type utilizing a water cooled condenser, but an arrangement employing an air cooled condenser may be 30 used if desired. In the device shown in the draw-. ings, the motor driven compressor is connectedI with a cooling coil 30 provided with a plurality of/ closely spaced ns 34 located in the upper compartment by the suction conduit 2l. From the 35 compressor the refrigerant is conducted through the condenser I2 to the receiver I3 from which it is supplied, through expansion valve 28, to the coil 30, where it expands-and absorbs heat from air circulated through the coil. The heat so absorbed by the refrigerant is given off in the cyclic process of subsequent compression and passage throughthe condenser back tothe receiver. The refrigerating structure and its operation is the same as that of the well known commercial types of its kind except as regards the structure and operation characteristic of the finned coil evaporator in the air conditioning or upper chamber presently to be described.

The'complete conditioning of air within the apparatus and the circulationiof air therefrom takes place in the upper compartment of the cabinet or casing. In the air conditioning process, air taken in at the rear of the structure is ltered by the filter 36, dehydrated and cooled by the nned coil structure 30-34, mixed with an ionized portion of air from ionizing means 3l, and is then circulated through all sections of the lower stratas of the enclosure by the oscillating fan or blower 38. The structural arrangement and organization of the conditioning units form important features of the invention. To provide for circulation of the air through the upper compartment of the structure the front upper part of the cabinet or casing is provided with a grilled opening 3| therein above the supporting shelf or partition 4. 'I'he overlying grill 32 may be of expanded metal or any reticulated screen structure and serves as a guard for the oscillating motor driven air circulating fan mounted behind the grill. The rear panel I5 is removable from the cabinet to provide access to the apparatus and in normal position closes the lower and upper compartments except that it is provided with an air intake-opening 33 in its upper part above 75 the horizontal shelf. The air lter-36 overlies this opening and the size and shape of the intake opening in the rear panel is such as to direct the air entering the apparatus through the filter and directly over the evaporator including coil :it and its fin structures 3d.

The nned coil evaporator of the invention, its

structural cooperation with other features of the .air conditioning apparatus, and the method of preventing accumulation of moisture on the evaporator, form important features of the invention. As previously explained above, structures of the prior art have operated with a great loss of emciency due to their structural limitations and the absence of method for disposing of moisture as it tends to accumulate on the coil and iin surfaces. If moisture accumulates on the coil and iin surfaces. it immediately tends toinsulate these members with the result that the air contacting surfaces soon go above the dew point as moisture accumulates, preventing further and continuous dehydration. With the low side evaporator of this invention it is possible to maintain air contacting surfaces of the coil and extended iins below dew point and to continuously hold the temperature of the air lower, for example, approximately 40 degrees instead of 48 to 50 degrees, as has been possible in structures heretofore employed, thus materially increasing the efficiency of the apparatus. This has been accomplished by removing the moisture from the effective coil and iin surfaces as it accumulated to maintain the surfaces in condition for further and continuous moisture extraction from the aii` while the machine is in operation.

'The coil 30 is vertically disposed immediately in front of the filter t6 at the rear of the upper chamber above a condensation receiving receptacle or tray 39 supported on the horizontal partition of the casing. The coil is provided with a plurality 'of parallel vertical extended fins 34 so spaced as to define closely restricted passageways between the fins. These fins may be spaced approximately ten to fifteen to the inch and their assembly is so arranged as to overlie the lter.

and air intake opening in the rear panel so that air entering the compartment from the rear is caused to pass over the coil and fin surfaces before it is circulated from the apparatus back into.

place the condensation 'without employing more than the normal air stream induced by the fan entering the rear of the unit so that in actual operation the iin surfaces are constantly renewed for closer contact with the air passing the evaporator. In other words, at normal full load speed of the motor driving the fan, the airI moving through the evaporator from 100 to 125 ft. per minute results inimaintaining the fin surfaces clear of accumulated moisture. This elimination of moisture as it accumulates allows maintenance of the coil and fin structure below dew point and continued dehydration takes place during operation of the machine. A curved baille I0 draining downwardly into the receptacle or tray 39 extends longitudinally of the cabinet compartment in front of the lowermost or moisture draining section of the coil and fin assembly to preclude any possibility of projection of moisture from the lower end of the iins or from the tray into the room by the air circulating fan. Water from the tray is drained continuously through drainage connection M opening into the bottom of the tray and connected at its other end with a suitable outlet.

Forced circulation of air from the room or enclosure through the apparatus and recirculation of air entering through the front of the cabinet around the fan is obtained by the oscillating fan driven by electric motor 42. This fan is located centrally of the cabinet so as to oscillate back and forth across thegrilled opening in the front of the cabinet. Cooled air issuing from the device instead of being directed toward the ceiling of the room, as has been the practice with prior air conditioning arrangements, is discharged in the lower strata of the room. After the dehumidification process has taken place this produces a very pronounced temperature difference between the lower and upper strata of air in the room. This temperature difference generally amounts to from eight to ten degrees Fahrenheit. Another important feature of the air circulating arrangement is that approximately only one fourth of the air circulated by the fan comes through the iilter and refrigerating coil. The remainder of the air is a recirculation of air from the enclosure coming in at the front of theI cabinet and then out by the various oscillations of the fan. This provides for tempering the cool air streamfrom the evaporator by air from the room before it leaves the machine, which avoids creation of a cold draft on any occupant of the room. For example, approximately one fourth of the circulated air from the machine ponies olf the coil at a approximately 42, butdue to the fact thaty this air is tempered by air from the room, by action of the oscillating fan, the air i issuing from the front of the cabinet will only be from eight to ten degrees below'room temperature. The directing of the conditioned air into the lower strata of the enclosure makes it un- I of this invention will take care of more area per capacity of 'machine than units heretofore employed in the art. During the dehumidifying process the lower air is first dehumidifled and the upper air becoming relatively heavier begins to come down so that eventually dehumidication of all the air within the enclosure takes place,I

forms a very important feature of the invention.

In conditioning air within an enclosure or room, it is necessary to deal with contamination and malodorous impurities, caused by pollens, body odors, tobacco smoke, breathing of occupants, traiilc odors and other agencies. Merely filtering or'washing the' air does not effectively solve i the problem. It has been the practice to bring in from twenty-live to thirty percent of outside air to eliminate accumulation of odor within an occupied space being conditioned. This practice has necessitated larger installations of equlpment to carry the extra load costing the consumer not only an additional cost in the initial installation but also a similar additional cost in the operation of the apparatus. The present invention obviates the necessity of utilizing this additional load of outside air by purifying the air within the enclosure. This is accomplished by inclusion of an air ionizing process whereby a portion of the air circulated is ionized and mingled with other treated air issuing from the machine. Ihe ionizing or ozonating apparatus comprises an ozone generator 31 and transformer 44 having its primary winding included in an electric circuit extending into the upper compartment from the junction box in the lower compartment of the unit. The secondary winding of the transformer serves to supply a small but high voltage current to spaced electrodes 45 and 46 separated by a glass tube to produce a corona discharge between the electrodes. The generator provides space for circulation of a layer of air which passes through the generator'to mix with the air stream projected by the circulating fan. The discharge between electrodes passes through the air in the generatonionizing and producing ozone in a well known manner. This ozone is discharged into the air stream passing through the air conditioning chamber to perform its function in purification of the air to be conditioned. The ozone generator is carefully de- A signed to maintain an evenly distributed discharge correctly proportioned to maintain proper' -air condition, and the discharge of the fons in the air aids materially in conditioning.

The ozone added to air` oxldizes completely all impurities of organic nature or converts them into some inert product not capable of further oxidation, which, due to ionization, readily filter out and the ozone has the chemical ability to oxidize even the most minute traces of certain malodorous constituents of bad air. Oxidization of almost all forms of organic matter by ozone is true not only for high concentrations of ozone but it is true also for ozone at such high dilutions as one part ozone to one million parts of air. The amount of ozone generated and mixed with the air leaving the conditioning unit of the invention results in such low concentration in the atmosphere within the room as to be harmless and undetectable by an occupant of the room. However, even in this very low concentration, the addition of ozone to the dehumidied air results in removal of unpleasant effects and renders an odorless, more invigorating and cleaner air in the room, for ozone is the most powerful oxidizing agent known and so active that it purifies air even when so dilute as to be undetectable. In low concentrations such as are employed in the air conditioning apparatus of this invention, ozone has a distinctive characteristic and pleasing odor producing a refreshing, bracing, pungent and exhilarating atmosphere. In addition to oxidizing' impurities of organic nature in the air, the ionization frees physical particles from their protective coatings of absorbed gases so that there particles more readily adhere to various surfaces. In this respect, the ionization phase materially assists filtration and the filtration mutually aids ionization. For example, in dealing with tobacco smoke which comprises in part minute particles of matter suspended in atmosphere, the minute particles are precipitated out and in some cases join so that these particles due to the ionization readily deposit themselves on surfaces such as the filter where they are more easily retained, thus eliminating their suspension in the atmosphere.

The ionization operation has a true cooperation with that of filtration and allows accomplishment of practically complete ltration -not obtainable without accompanying ionization.

It is apparent from the foregoing detailed description ofthe apparatus and its operation that the invention provides a compact unitary air conditioning device, the relative eiciency of which is increased materially over structures of the prior art. The-structural combination may be employed in structural arrangements other than the cabinet illustrated, for the unit may be built into a wall of the room or may be employed otherwise in conjunction with original fabrication of buildings. In the system as described, however, the collective provisions of, the method of preventing accumulation of moisture on the evaporator so as to provide continuous and unimpaired dehydration, the improved circulation in the lower strata of the air by an oscillating fan whereby the larger portion of circulating air stream is recirculated tempering air entering the front of the unit from the room, the filtering of air entering the rear of the cabinet, and the discharge into the air circulated from the unit of such a portion of ionized air as will deal with malodorous impurities and prevent their accumulation and aid filtration, affords a unitary type of air conditioning machine which can be used within a room or enclosure to produce a new result in maintaining comfortable and clean air within the room. Eliminating the necessity of leading in a fresh air supply, and confining the major cooling to the lower strata or zone of occupancy without producing cold drafts, allows conditioning, from the standpoint of comfort cooling, of more space per unit capacity than would otherwise be possible and materially reduces air conditioning cost in the cost of operating and in the initial installation.

While the invention is hereinbefore described in connection with a preferred embodiment, it'is to be understood that the words which have been used are words of description rather than of limitation and that changes within the purview of the appended claims may be made without departing from the true scope and spirit of the invention in all its aspects.

I claim:

1. The method of conditioning air within a room or enclosure which comprises circulating a stream of the air through a housing within the enclosure, dehumidifying and cooling the stream of air, ionizing a portion of the air within the housing, and mixing with the stream of cooled aira larger -volume of tempering air from the enclosure at higher temperature before the combined air stream leaves the housing.

2. The method of conditioning air within an enclosure which comprises circulating a stream of air through a housing defining a confined space within the enclosure, filtering minute particles out of the air stream in the confined space, cooling and dehydrating the air stream passing through the confined space, adding ozone to the air stream, and tempering the cooled air stream before leaving the confined space with a larger volume of higher temperature air from the enclosure.

3. 'I'he method of conditioning with a unitary device the volume of air within an enclosure which comprises filtering a portion of a moving stream of the air within the device, dehydrating and 75 acter described, a housing having air inlet and air outlet openings, means for filtering out minute rparticles in air entering .the inlet opening, means for dehumidifying and cooling the air entering the housing from the filter in separate air streams not substantially less than nine to the inch, means Within the housing for ionizing air, and an oscillating mot-or driven oscillating fan for circulating a stream of air through the apparatus.

5. In a unitary air conditioning device, a casing defining an air conditioning compartment having air inlet and air outlet openings, means for filtering air entering the inlet opening, means for dehumidifying and cooling air which passes the lter, said last mentioned means including a plurality of extended vertical iins spaced substantialiy not less than ten to the inch defining relatively narrow air passages between iin surfaces, refrigerating apparatus connected withsaid cooling and dehydrating means, an ozone generator within the compartment, and an oscillating fan arranged to swing across the air outlet opening of the casing and circulate a stream of air through the outlet opening of the conditioning compartment into the lower strata of an enclosure.

6. A complete air conditioning unit for conditioning the confined volume of air within an en-` a stream of air from the evaporator and a larger body of tempering air from the enclosure from the housing into the lower strata of the enclosure, said circulating means including an oscillating fan.

7. A complete air conditioning unit for conditioning the conned volume of air within an enclosure comprising a housing support having upper and lower compartments therein and air inlet and outlet openings communicating with the upper compartment, a nned ,coil cooling evaporator overlying the inlet opening of the housing, the ns of the evaporator being so closely spaced as to define narrow restricted air passages between surfaces of the fins, refrigerating apparatus in the lower-compartment of the cabinet connected with the evaporator, means for generating ozone in the upper compartment and an oscillating motor driven fan in the upper compartment for mixing with the cooled air stream a larger volume of Itempering air from the enclosure and for circulating the resulting air stream throughout the lower strata of the enclosure.

8. A. unitary air conditioning apparatus for conditioning the oonild volume ot air within an enclosure comprising a cabinet having an air inlet opening and an air outlet opening, a cooling evaporator having a plurality of parallel vertical extended fins overlying the air inlet opening, said lns being spaced from ten to fifteen to the inch to define restricted air passages through the evaporator, an ozonefgenerator within the cabinet and a circulating fan for circulating air from the cabinet through the air outlet opening into the lower strata of the. enclosure, said fan and cooling evaporator being so arranged that the circulating stream of air induced by the fan maintains the surfaces of the iins free from moisture accumulations: 4

9. `In an air conditioning apparatus of the character described, an air conditioning chamber, means for circulating a stream of air through the chamber, dehumidifying and cooling means for contacting theu circulating air stream in passage through the chamber, said dehumidifying and cooling means including a plurality of extended surfaces with air passages therebetween so restricted that air passing between the surfaces displaces moisture accumulation from the surfaces, means for ionizing a portion of the airto oxidize organic impurities in the air and to precipitate minute particles, and a filter for ltering minute particles from the circulated air stream.

10. Air conditioning apparatus comprising a conditioning chamber having air inlet and outlet openings, a fan for circulating a stream of air through the chamber, a llter over the air inlet opening, means for dehumidifying and cooling the circulated stream of air, said means including a plurality of extended vertical iin surfaces with air passages therebetween so small that the passage of air over said ns prevents accumulation of moisture on the iin surfaces, means for collecting moisture descending from the iins, said means including an upwardly extending moisture collecting baiiie between the fan and the lower portion of the cooling means, and an ozone generator for supplying ozone to the air stream.

11. In a unitary air conditioning apparatus for conditioning air in an enclosure, a housing having air inlet and air outlet openings, means for filtering air entering the inlet opening, means for dehumidifying and cooling air which passes the illter, said last mentioned means including' a plumeans and the air outlet opening for circulating a stream of air through the housing and mixing therewith tempering air from` the enclosure,

and means for controlling operation of the ionizing means and circulating means alone lor in combination with the refrigerating means.

12. In air conditioning apparatus, a housing having air inlet and air outlet openings, means for filtering out minute particles in air entering the inlet opening, means for dehumidifying and cooling the air entering the housing from the filter, refrigeration apparatus connected with said last mentioned means, means for ionizing air in the housing, a motor driven fan for circulating a stream of air through the housing, and means for controlling operation of the ionizing means and fan alone or'in combination with the refrigerating means. 

